Various key and cylinder locking systems are known where the locking cylinder is exposed so that a key can be inserted to unlock the device. Such systems can be relatively easily picked or tampered with by inserting a slender object into the cylinder opening. Recently it has been shown that even a pen can open some known locking systems.
Forcing a sharp-pointed object into the cylinder opening can also easily damage Key and cylinder systems. Key and cylinder systems are large and bulky and are not practical in many applications where space is not available such as bicycle wheels.
There is a need for a locking system that is more secure and theft resistant than traditional key and cylinder systems.